A method and system for calibrating an in-situ mechanical probe in a simulated seabed environment

Abstract

The present invention discloses a method and system for calibrating an in-situ mechanical probe in a simulated seabed environment. The method includes: selecting calibration parameters and setting the maximum load of the calibrated probe, dividing the calibration load value into multiple levels according to the maximum load of the calibrated probe; applying environmental external pressure to the calibrated probe; loading the calibrated probe with calibration loads step by step from low to high according to the divided calibration load values ​​and recording the detection values; after loading to the set maximum load, unloading the load step by step and recording the detection values ​​when unloading to each load value; repeating the process of loading\unloading the load several times, and performing error analysis on the calibrated probe according to the recorded detection values. The present invention can simulate the environmental pressure of the seabed for the probe during the calibration process, and realize the automatic calibration of the three parameters of the cone tip resistance, side wall friction, and pore water pressure of the pore pressure static penetration probe, thereby improving the calibration efficiency and reducing the calibration error.

Description

Technical Field

[0001] The present invention relates to the technical field of marine geological survey, and in particular to an in-situ mechanical probe calibration method and system for simulating a seabed environment. Background Art

[0002] With the rapid development of marine engineering construction (bridges, offshore platforms, wind power, submarine cables, etc.) and seabed resource exploration (petroleum, methane hydrate, manganese-cobalt nodules, deep-sea rare earths, etc.), it is particularly important to obtain high-quality physical parameters of underwater rock and soil. Due to the particularity of river, lake and marine engineering geology, especially in deepwater areas, it is difficult and costly to take samples on site and maintain the stress state of the original soil. The pore pressure penetration test (CPTU) can minimize the disturbance of the original structure of the rock and soil and the release of in-situ stress caused by drilling, sampling, transportation and other operation processes. At present, the application of CPTU technology is becoming more and more extensive. Facing the complex and high-pressure deep-sea environment, the development of a new seabed in-situ mechanical probe calibration system is an important foundation.

[0003] However, although the current conventional probe calibration devices can complete the calibration of cone tip resistance, side wall friction and pore water pressure, they cannot simulate the deep sea environment, resulting in a lack of pressure environment for simulating the probe working on the seabed and unable to eliminate the impact of environmental pressure on probe data. In addition, the above devices still require manual operation for calibration, which is relatively inefficient. Summary of the invention

[0004] The purpose of the present invention is to provide a method and system for calibrating an in-situ mechanical probe in a simulated seabed environment, so as to solve one or more technical problems existing in the above-mentioned background technology.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A method for calibrating an in-situ mechanical probe in a simulated seabed environment, the method comprising:

[0007] Select calibration parameters and set the maximum load of the calibrated probe, and divide the calibration load value into multiple levels according to the maximum load of the calibrated probe, wherein the calibration parameters include cone tip resistance, side wall friction, and pore water pressure;

[0008] Install the probe to be calibrated, and then apply ambient external pressure to the probe to be calibrated;

[0009] According to the divided calibration load values, the calibration load is applied to the calibrated probe step by step from low to high, and the detection value of the calibrated probe itself and the detection value of the force applied to the probe by the sensor are recorded when the load value is reached.

[0010] After loading to the set maximum load, unload the load step by step and record the detection value of the calibrated probe itself and the detection value of the sensor on the force of the probe when unloading to each load value;

[0011] Repeat the above loading\unloading process several times, perform error analysis on the calibrated probe based on the recorded test values, and calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe.

[0012] Preferably, in this method, if the calibration parameter is selected as the cone tip resistance, the loading / unloading load acts on the cone tip of the calibrated probe, and after loading / unloading the load, the sensor's detection value of the probe force and the cone tip resistance value read by the calibrated probe are recorded;

[0013] If the calibration parameter is sidewall friction, first fit the sidewall pad to the outside of the probe to be calibrated, and apply the loading / unloading load to the sidewall sleeve of the probe to be calibrated through the sidewall pad. After loading / unloading the load, record the sensor's detection value of the probe force and the sidewall friction value read by the probe to be calibrated.

[0014] If the calibration parameter is pore water pressure, the loading / unloading pressure acts on the internal differential pressure sensor through the permeable stone of the probe. After loading / unloading, the pressure difference between the first cabin where the calibrated probe is located and the second cabin where the permeable stone of the calibrated probe is located, as well as the pore water pressure value read by the calibrated probe are recorded.

[0015] Preferably, during the error analysis, the force exerted on the cone tip by the external force of the environment in the opposite direction to the loading load is calculated, and the influence of the force on the detection value of the force exerted on the probe by the sensor is eliminated.

[0016] Preferably, when performing error analysis on the calibrated probe, the calibration parameters are first fitted to obtain a theoretical curve, and the sensor data obtained in the calibration process and the calibrated probe data are averaged to obtain discrete data [(x1, y1), (x2, y2) ... (xi, yi)], and the discrete data is one-dimensionally linearly distributed, and the fitting straight line expression is set as:

[0017] Y=a0+a1x

[0018] Based on the principle of least squares method, the unknowns a0 and a1 are determined by minimizing the sum of squares of the equation errors. The square sum of the difference between the function Y and the output value of the calibrated probe is expressed as follows:

[0019]

[0020] Find the partial derivative of a0 and a1 in the above formula and make its partial derivative value 0, and we get:

[0021]

[0022] Expand to:

[0023]

[0024] Solving the equation, we can get the coefficients a0 and a1, and substituting them into Y can get the fitting straight line of the corresponding discrete data.

[0025] Preferably, a sensor calibration curve is obtained according to the loading / unloading load value and the value read by the sensor. According to the sensor calibration curve and the fitting curve, the nonlinear error of the calibrated probe can be obtained as follows:

[0026] δ=H1 / Y max *100%

[0027] Where: δ is the nonlinear error; H1 is the maximum deviation between the calibration curve and the fitting straight line; Y max is the maximum output of full scale;

[0028] The hysteresis error of the calibrated probe is:

[0029] r H =H2 / Y max *100%

[0030] Where: r H is the hysteresis error; H2 is the maximum output difference of the forward and reverse strokes;

[0031] The repeatability error of the calibrated probe is:

[0032] r R =H3 / Y max *100%

[0033] Where: r R is the repeatability error; H3 is the maximum difference in pressurization or pressure relief output under the same load.

[0034] Preferably, when the loading\unloading load is close to the calibrated load value, the loading\unloading speed of the load is reduced. After the calibration of a load value is completed, the loading\unloading speed of the load is increased until the loading\unloading load is close to the next calibrated load value.

[0035] The present invention also provides an in-situ mechanical probe calibration system for simulating a seabed environment, comprising a calibration device, a hydraulic device, a central control panel, a data acquisition panel and an integrated acquisition machine;

[0036] The calibration device is used to install the probe to be calibrated;

[0037] The hydraulic device is used to apply environmental external pressure to the calibrated probe; and is used to load the calibrated probe with a calibration load according to the set maximum load value and calibration parameters;

[0038] The central control board is used to control the hydraulic device to load / unload the load and record the sensor's force detection value on the probe and transmit the detection data to the data acquisition board;

[0039] The data acquisition board is used to record the detection value of the calibrated probe itself when loading / unloading the load and upload the sensor detection value and the probe detection data to the acquisition integrated machine via Bluetooth;

[0040] The integrated acquisition machine is used to receive the sensor detection values ​​and probe detection values ​​uploaded by the data acquisition board and calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe.

[0041] Preferably, the calibration device includes a first cabin, a second cabin and a third cabin, the first cabin and the second cabin are arranged up and down, the first cabin needs to be connected to the second cabin when calibrating the cone tip resistance and the side wall friction, and the first cabin is not connected to the second cabin when calibrating the pore water pressure, the first cabin and the second cabin are used to accommodate the calibrated probe, the pore of the calibrated probe is located in the second cabin, the third cabin is arranged below the second cabin, and the third cabin is used to accommodate the telescopic end of the hydraulic device.

[0042] Preferably, the hydraulic device includes a pressure cylinder, a thrust piston and a pressure pump, the thrust piston is arranged in the third cabin, the output end of the pressure cylinder is connected to the thrust piston, and the pressure cylinder is used to drive the thrust piston to extend or retract to load / unload the cone tip of the calibrated probe; the first output end and the second output end of the pressure pump are respectively connected to the first cabin and the second cabin to apply ambient external pressure to the calibrated probe and load / unload the pores of the calibrated probe, and the second cabin is also provided with a side wall pad that can move radially along the calibrated probe.

[0043] Preferably, the central control panel includes a weighing sensor and a pressure sensor. The pressure sensor is arranged in the pressure pump and the hydraulic device. The pressure sensor is used to detect the internal pressure of the second cabin. The weighing sensor is arranged on the top of the thrust piston.

[0044] The beneficial effects of the present invention are as follows: the present invention can simulate the environmental pressure of the seabed for the probe during the calibration process, and realize the automatic calibration of the three parameters of the pore pressure static penetration probe cone tip resistance, side wall friction, and pore water pressure, thereby improving the calibration efficiency and reducing the calibration error, and providing the necessary technical means for the optimization and mass production of pore pressure static penetration probes. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings further illustrate the present invention, but the contents in the accompanying drawings do not constitute any limitation to the present invention.

[0046] Figure 1 is a flow chart of a calibration method according to one embodiment of the present invention;

[0047] Figure 2 is a schematic diagram of a calibration curve and a fitting straight line generated during a calibration process of one embodiment of the present invention;

[0048] Figure 3 It is a numerical relationship diagram of the load on the calibrated probe and the detection output of the calibrated probe itself before the dead zone is removed in one embodiment of the present invention;

[0049] Figure 4 It is a numerical relationship diagram of the load on the calibrated probe and the detection output of the calibrated probe itself after removing the dead zone in one embodiment of the present invention;

[0050] Figure 5 It is a schematic diagram of the system composition of the calibration system of the present invention;

[0051] Figure 6 It is a schematic diagram of the working principle of the hydraulic device and the calibration device of the calibration system of the present invention;

[0052] Figure 7 It is a schematic diagram of the principle of the calibration system of the present invention in calibrating the side wall friction force of the probe.

[0053] Among them: calibration device 1, hydraulic device 2, central control board 3, data acquisition board 4, integrated acquisition machine 5, calibrated probe 6, cone tip 61, first cabin 11, second cabin 12, third cabin 13, side wall pad 14, thrust piston 21, pressurizing cylinder 22, weighing sensor 31, pressure sensor 32. DETAILED DESCRIPTION

[0054] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0055] Example 1

[0056] A method for calibrating an in-situ mechanical probe in a simulated seabed environment in this embodiment is shown in the attached Figure 1 , the method comprising:

[0057] Select calibration parameters and set the maximum load of the probe to be calibrated. The calibration load value is divided into multiple levels according to the maximum load of the probe to be calibrated. The calibration parameters include cone tip resistance, side wall friction, and pore water pressure.

[0058] Install the probe to be calibrated, and then apply ambient external pressure to the probe to be calibrated;

[0059] According to the divided calibration load values, the calibration load is applied to the calibrated probe step by step from low to high, and the detection value of the calibrated probe itself and the detection value of the force applied to the probe by the sensor are recorded when the load value is reached.

[0060] After loading to the set maximum load, unload the load step by step and record the detection value of the calibrated probe itself and the detection value of the sensor on the force of the probe when unloading to each load value;

[0061] Repeat the above loading\unloading process several times, perform error analysis on the calibrated probe based on the recorded test values, and calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe.

[0062] Therefore, by applying environmental external pressure to the calibrated probe and then applying the set load to the calibrated probe in turn, the automatic calibration of the three parameters of the pore water pressure, the cone tip resistance, the side wall friction and the pore water pressure of the pore pressure static penetration probe can be achieved; by repeatedly loading and unloading the load several times during the calibration process, the calibration accuracy is improved, thereby providing the necessary technical means for the optimization and mass production of pore pressure static penetration probes.

[0063] Preferably, in this method, if the calibration parameter is selected as the cone tip resistance, the loading / unloading load acts on the cone tip of the calibrated probe, and after loading / unloading the load, the sensor's detection value of the probe force and the cone tip resistance value read by the calibrated probe are recorded;

[0064] If the calibration parameter is sidewall friction, first fit the sidewall pad to the outside of the probe, and apply the loading / unloading load to the sidewall sleeve of the probe to be calibrated through the sidewall pad. After loading / unloading the load, record the sensor's detection value of the probe force and the sidewall friction value read by the probe to be calibrated.

[0065] If the calibration parameter is pore water pressure, the loading / unloading pressure acts on the internal differential pressure sensor through the permeable stone of the probe. After loading / unloading, the pressure difference between the first cabin and the second cabin and the pore water pressure value read by the calibrated probe are recorded.

[0066] Therefore, according to different calibration parameters, the load can be loaded and unloaded at different positions of the calibrated probe without manual operation. By recording the readings of the sensor and the calibrated probe itself, data is provided for the subsequent calculation of nonlinear error, hysteresis error and repeatability error, so as to realize automatic calibration of each calibration parameter and improve the efficiency of calibration.

[0067] Preferably, during the error analysis, the force exerted on the cone tip by the external force of the environment in the opposite direction to the applied load is calculated to remove the influence of the force on the sensor's detection value of the probe force. Figure 3 As shown in the figure, the horizontal axis is the loaded load value, and the vertical axis is the output value detected by the calibrated probe itself. Curves of different line types represent probes subjected to different environmental external pressure values. It can be seen that the output value detected by the calibrated probe itself remains unchanged at first and then rises as the load increases. This is due to the existence of a dead zone inside the device. The dead zone occurs because when there is a certain environmental pressure in the space where the calibrated probe is located, a force opposite to the loaded load will be generated on the cone tip. Therefore, the load loaded on the calibrated probe will first offset the environmental pressure before it will generate a force on the probe. As the environmental pressure increases, the greater the force required to offset, the larger the dead zone in the image. Therefore, this embodiment calculates the force generated by the external environmental force on the cone tip in the opposite direction to the applied load, and removes the influence of the dead zone according to the calculation result during calibration to ensure the accuracy of the data. The specific calculation method is to measure the effective contact area between the cone tip and the second cabin. After calculation, the force generated on the cone tip under different environmental pressures can be obtained. After removal, Figure 4 shown.

[0068] Preferably, when performing error analysis on the calibrated probe, the calibration parameters are first fitted to obtain a theoretical curve, and the sensor data obtained in the calibration process and the calibrated probe data are averaged to obtain discrete data [(x1, y1), (x2, y2) ... (xi, yi)], and the discrete data is one-dimensionally linearly distributed, and the fitting straight line expression is set as:

[0069] Y=a0+a1x

[0070] Based on the principle of least squares method, the unknowns a0 and a1 are determined by minimizing the sum of squares of the equation errors. The square sum of the difference between the function Y and the output value of the calibrated probe is expressed as follows:

[0071]

[0072] Find the partial derivative of a0 and a1 in the above formula and make its partial derivative value 0, and we get:

[0073]

[0074] Expand to:

[0075]

[0076] The coefficients a0 and a1 can be obtained by solving the equation and can be substituted into Y to obtain the fitting straight line of the corresponding discrete data. This embodiment uses the least squares method to fit the calibration data to obtain the theoretical curve, and uses the linear regression method to obtain the nonlinear error, repeatability error, and hysteresis error of the calibration data.

[0077] Furthermore, the sensor calibration curve is obtained based on the loading / unloading load value and the sensor reading value. Figure 2 According to the sensor calibration curve and the fitting curve, the nonlinear error of the calibrated probe can be obtained as follows:

[0078] δ=H1 / Y max *100%

[0079] Where: δ is the nonlinear error; H1 is the maximum deviation between the calibration curve and the fitting straight line; Y max is the maximum output of full scale;

[0080] The hysteresis error of the calibrated probe is:

[0081] r H =H2 / Y max *100%

[0082] Where: r H is the hysteresis error; H2 is the maximum output difference of the forward and reverse strokes;

[0083] The repeatability error of the calibrated probe is:

[0084] r R =H3 / Y max *100%

[0085] Where: r R is the repeatability error; H3 is the maximum difference in pressurization or pressure relief output under the same load.

[0086] Preferably, when the loading\unloading load is close to the calibrated load value, the loading\unloading speed of the load is reduced to ensure that data can be collected normally. After the calibration of a load value is completed, the loading\unloading speed of the load is increased until the loaded\unloading load is close to the next calibrated load value to ensure calibration efficiency.

[0087] Example 2

[0088] A calibration system for in-situ mechanical probes simulating a submarine environment. Figure 5 , including a calibration device 1, a hydraulic device 2, a central control board 3, a data acquisition board 4 and an integrated data acquisition machine 5;

[0089] The calibration device 1 is used to install the probe 6 to be calibrated;

[0090] The hydraulic device 2 is used to apply ambient external pressure to the calibrated probe 6; and is used to load the calibrated probe 6 with a calibration load according to the set maximum load value and calibration parameters;

[0091] The central control board 3 is used to control the hydraulic system to load / unload the load and record the sensor's force detection value on the probe and transmit this detection data to the data acquisition board;

[0092] The data acquisition board 4 is used to record the detection value of the calibrated probe 6 itself when loading / unloading the load and upload the sensor detection value and the detection data of the probe 6 to the collection integrated machine via Bluetooth;

[0093] The integrated data acquisition machine 5 is used to receive the sensor detection values ​​and probe detection values ​​uploaded by the data acquisition board and calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe 6.

[0094] Compared with conventional calibration devices, the calibration system of this embodiment has the advantages of automatic load application, can simulate environmental pressures such as 30MPa on the seabed, and has the advantages of automatic data recording. The calibration system and the conventional calibration device 1 both take about 2 hours to complete the calibration of a probe, but the conventional calibration device 1 requires two staff members (one to apply load and one to record data) to cooperate to complete the calibration of a probe, while the calibration system only requires one staff member to complete the calibration operation, thereby multiple calibration systems can be used to simultaneously complete the calibration of multiple probes, realizing mass production of probes.

[0095] Preferably, refer to the attached Figure 6 The calibration device 1 includes a first cabin 11, a second cabin 12 and a third cabin 13. The first cabin 11 and the second cabin 12 are arranged up and down. When calibrating the cone tip resistance and the side wall friction, the first cabin 11 and the second cabin 12 need to be connected by a three-way valve to ensure that the environmental pressure at the head and tail of the probe is consistent. When calibrating the pore water pressure, the first cabin 11 and the second cabin 12 are not connected. At this time, the probe is calibrated with the difference between the first cabin 11 and the second cabin 12. The first cabin 11 and the second cabin 12 are used to accommodate the calibrated probe, and the pore of the calibrated probe is located in the second cabin 12. The third cabin 13 is arranged below the second cabin 12, and the third cabin 13 is used to accommodate the telescopic end of the hydraulic device.

[0096] By installing the probe 6 to be calibrated in the inner cavity formed by the first cabin 11 and the second cabin 12, it is convenient to apply a certain external environmental pressure to the probe 6 to be calibrated during the calibration process, thereby forming an effect of simulating the seabed pressure; after the probe 6 to be calibrated is installed, the pore of the probe 6 to be calibrated is located in the second cabin 12, so that the calibration of the probe pore water pressure can be achieved by pressurizing the second cabin 12. The third cabin 13 is arranged below the second cabin 12, and is used to accommodate the telescopic end of the hydraulic device 2, so that the telescopic end of the hydraulic device 2 moves closer to or away from the cone tip 61 of the calibrated probe 6 when telescoping, thereby achieving automatic calibration of the resistance of the probe cone tip 61 and the friction of the side wall.

[0097] Furthermore, the hydraulic device 2 includes a pressure cylinder 22, a thrust piston 21 and a pressure pump. The thrust piston 21 is arranged in the third cabin 13. The output end of the pressure cylinder 22 is connected to the thrust piston 21. The pressure cylinder 22 is used to drive the thrust piston 21 to extend or retract so as to load / unload the cone tip 61 of the calibrated probe 6; the first output end and the second output end of the pressure pump are respectively connected to the first cabin 11 and the second cabin 12 to apply ambient external pressure to the calibrated probe 6 and load / unload the pores of the calibrated probe 6. The second cabin 12 is also provided with a side wall pad 14 that can move radially along the calibrated probe 6.

[0098] The thrust piston 21 is driven to extend and retract by the pressure cylinder 22, so that the thrust piston 21 applies a load to the cone tip 61 of the probe 6 to be calibrated, thereby achieving the calibration of the resistance parameter of the cone tip 61 of the probe; the movable side wall pad 14 is attached to the outer side of the probe 6 to be calibrated, and the load is applied to the cone tip 61 of the probe 6 to be calibrated. Figure 7 The thrust piston 21 is driven to extend and retract through the pressure cylinder 22, and the side wall sleeve of the calibrated probe 16 is applied through the side wall pad 14 to calibrate the side wall friction force parameters of the probe; the pore water pressure parameters of the calibrated probe 6 are calibrated by applying pressure to the second cabin 12 through the pressure pump.

[0099] Furthermore, the central control panel 3 includes a weighing sensor 31 and a pressure sensor 32. The pressure sensor 32 is arranged in the pressure pump and the hydraulic device. The pressure sensor 32 is used to detect the internal pressure of the second cabin 12. The weighing sensor 31 is arranged on the top of the thrust piston 21. When the calibration parameter is selected as the cone tip 61 resistance or the side wall friction, the weighing sensor 31 detects the force between the cone tip 61 of the calibrated probe 6 and the thrust piston 21 to achieve the calibration of the probe cone tip 61 resistance and the side wall friction. When the calibration parameter is selected as the pore water pressure, the first cabin 11 and the second cabin 12 are first pressurized to the predetermined value of the simulated seabed pressure environment by the pressure pump, and then the pressure of the first cabin 11 is kept unchanged during the calibration process, and the second cabin 12 is pressurized and released to achieve the calibration of the probe pore water pressure parameter.

[0100] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. A method for calibrating an in-situ mechanical probe in a simulated seabed environment, characterized in that: The method includes: Select calibration parameters and set the maximum load of the calibrated probe, and divide the calibration load value into multiple levels according to the maximum load of the calibrated probe, wherein the calibration parameters include cone tip resistance, side wall friction, and pore water pressure; Install the probe to be calibrated, and then apply ambient external pressure to the probe to be calibrated; According to the divided calibration load values, the calibration load is applied to the calibrated probe step by step from low to high, and the detection value of the calibrated probe itself and the detection value of the force applied to the probe by the sensor are recorded when the load value is reached. After loading to the set maximum load, unload the load step by step and record the detection value of the calibrated probe itself and the detection value of the sensor on the force of the probe when unloading to each load value; Repeat the above loading and unloading process several times, perform error analysis on the calibrated probe according to the recorded test values, and calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe; When performing error analysis on the calibrated probe, first fit the calibration parameters to obtain a theoretical curve, and then average the sensor data obtained during the calibration process and the calibrated probe data to obtain discrete data [(x1, y1), (x2, y2)...(xi, yi)]. The discrete data is distributed in a one-dimensional linear manner, and the fitting straight line expression is set as: Y=a0+a1x Based on the principle of least squares method, the unknowns a0 and a1 are determined by minimizing the sum of squares of the equation errors. The square sum of the difference between the function Y and the output value of the calibrated probe is expressed as follows: Find the partial derivative of a0 and a1 in the above formula and make its partial derivative value 0, and we get: Expand to: Solving the equation, we can get the coefficients a0 and a1, and substituting them into Y can get the fitting straight line of the corresponding discrete data; The sensor calibration curve is obtained according to the loading / unloading load value and the value read by the sensor. According to the sensor calibration curve and the fitting curve, the nonlinear error of the calibrated probe can be obtained as follows: δ=H1 / Y max *100% Where: δ is the nonlinear error; H1 is the maximum deviation between the calibration curve and the fitting straight line; Y max is the maximum output of full scale; The hysteresis error of the calibrated probe is: r H =H2 / Y max *100% Where: r H is the hysteresis error; H2 is the maximum output difference of the forward and reverse strokes; The repeatability error of the calibrated probe is: r R =H3 / Y max *100% Where: r R is the repeatability error; H3 is the maximum difference in pressurization or pressure relief output under the same load.

2. The method for calibrating an in-situ mechanical probe in a simulated seabed environment according to claim 1, characterized in that: In this method, if the calibration parameter is selected as the cone tip resistance, the loading / unloading load acts on the cone tip of the calibrated probe. After loading / unloading the load, the sensor's detection value of the probe force and the cone tip resistance value read by the calibrated probe are recorded. If the calibration parameter is sidewall friction, first fit the sidewall pad to the outside of the probe to be calibrated, and apply the loading / unloading load to the sidewall sleeve of the probe to be calibrated through the sidewall pad. After loading / unloading the load, record the sensor's detection value of the probe force and the sidewall friction value read by the probe to be calibrated. If the calibration parameter is pore water pressure, the loading / unloading pressure acts on the internal differential pressure sensor through the permeable stone of the probe. After loading / unloading, the pressure difference between the first cabin where the calibrated probe is located and the second cabin where the permeable stone of the calibrated probe is located, as well as the pore water pressure value read by the calibrated probe are recorded.

3. The method for calibrating an in-situ mechanical probe in a simulated seabed environment according to claim 1, characterized in that: During the error analysis, the force exerted on the cone tip by the external force of the environment in the opposite direction to the loading direction is calculated, and the influence of the force on the detection value of the sensor on the force applied to the probe is eliminated.

4. The method for calibrating an in-situ mechanical probe in a simulated seabed environment according to claim 1, characterized in that: When the loading\unloading load is close to the calibrated load value, reduce the loading\unloading speed of the load. After the calibration of a load value is completed, increase the loading\unloading speed of the load until the loading\unloading load is close to the next calibrated load value.

5. An in-situ mechanical probe calibration system for simulating a seabed environment, characterized in that: Steps for implementing a method for calibrating an in-situ mechanical probe in a simulated seabed environment as described in any one of claims 1 to 4, wherein the system comprises a calibration device, a hydraulic device, a central control panel, a data acquisition panel and an integrated acquisition machine; The calibration device is used to install the probe to be calibrated; The hydraulic device is used to apply environmental external pressure to the calibrated probe; and is used to load the calibrated probe with a calibration load according to the set maximum load value and calibration parameters; The central control board is used to control the hydraulic device to load / unload the load and record the sensor's force detection value on the probe and transmit the detection data to the data acquisition board; The data acquisition board is used to record the detection value of the calibrated probe itself when loading / unloading the load and upload the sensor detection value and the probe detection data to the acquisition integrated machine via Bluetooth; The integrated acquisition machine is used to receive the sensor detection values ​​and probe detection values ​​uploaded by the data acquisition board to calculate the nonlinear error, hysteresis error and repeatability error of the calibrated parameters of the calibrated probe.

6. The in-situ mechanical probe calibration system for simulating a seabed environment according to claim 5, characterized in that: The calibration device includes a first cabin, a second cabin and a third cabin. The first cabin and the second cabin are arranged up and down. When calibrating the cone tip resistance and the side wall friction, the first cabin needs to be connected to the second cabin. When calibrating the pore water pressure, the first cabin is not connected to the second cabin. The first cabin and the second cabin are used to accommodate the calibrated probe. The pore of the calibrated probe is located in the second cabin. The third cabin is arranged below the second cabin. The third cabin is used to accommodate the telescopic end of the hydraulic device.

7. The in-situ mechanical probe calibration system for simulating a seabed environment according to claim 6, characterized in that: The hydraulic device includes a pressure cylinder, a thrust piston and a pressure pump. The thrust piston is arranged in the third cabin. The output end of the pressure cylinder is connected to the thrust piston. The pressure cylinder is used to drive the thrust piston to extend or retract to load / unload the cone tip of the calibrated probe; the first output end and the second output end of the pressure pump are respectively connected to the first cabin and the second cabin to apply environmental external pressure to the calibrated probe and load / unload the pores of the calibrated probe. The second cabin is also provided with a side wall pad that can move radially along the calibrated probe.

8. The in-situ mechanical probe calibration system for simulating a seabed environment according to claim 7, characterized in that: The central control panel includes a weighing sensor and a pressure sensor. The pressure sensor is arranged in the pressure pump and the hydraulic device. The pressure sensor is used to detect the internal pressure of the second cabin. The weighing sensor is arranged on the top of the thrust piston.

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